This year for the U.S. mint's 225th anniversary, the mint is planning to release an Enhanced Uncirculated coin set on the 1st of August. Each coin will be produced from the San Francisco mint and will have the 'S' mint mark.
The coin set includes the following,
- 2017-S Effigy Mounds National Monument Quarter (Iowa)
- 2017-S Frederick Douglass National Historic Site Quarter (Washington, DC)
- 2017-S Ozark National Scenic Riverways Quarter (Missouri)
- 2017-S Ellis Island (Statue of Liberty National Monument) Quarter (New Jersey)
- 2017-S George Rogers Clark National Historical Park Quarter (Indiana)
- 2017-S Native American $1 Coin, depicting Sequoyah writing “Sequoyah from Cherokee Nation” in syllabary along the border of the design
- 2017-S Kennedy half-dollar
- 2017-S Roosevelt dime
- 2017-S Jefferson nickel
- 2017-S Lincoln cent
A Proof coin has mirrored fields and frosted devices (relief). A Reverse Proof coin has the complete opposite of a Proof coin; mirrored devices and frosted fields. An Enhanced Uncirculated coin is a new kind of finish that the U.S. mint has come up with in recent years.
What is an Enhanced Uncirculated coin?
The Enhanced Uncirculated coin finish was created as a result of a customer feedback to the U.S. mint about some Proof coins. The frosting on Proof coins against mirrored fields seemed to affect the visibility of certain design elements in the coin. After a complete study at the Philadelphia mint, the mint officials found out that the issue was not in the design but rather in the way light was absorbed on the Proof coins' frosting surface. To overcome this, the mint came up with a new kind of coin finish called the Enhanced Uncirculated finish.
The Enhanced Uncirculated coin finish has lighter frosting or selectively frosted surfaces to contrast with the brilliantly polished or unpolished fields. This selective frosting and polished/unpolished finish can bring out certain designs in the coin better than in Proof coins.
For the U.S. Mint's 225th anniversary Enhanced Uncirculated set, the mint mentions that the set will have 'laser frosted areas and an unpolished field that accentuates design details creating a unique contrast distinctly different from the mirror-like finish of proof coins.'
It would be interesting to see how these coins will finally look compared to this year's Proof set that had the same set of coins and got released in March.